


Your Darkest Secret

by MissMollyBloom



Category: Sherlock (TV)
Genre: F/M, S4 Trailer reaction, Secret Relationship
Language: English
Status: In-Progress
Published: 2016-12-10
Updated: 2016-12-13
Packaged: 2018-09-07 18:04:57
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,178
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8810782
Author URL: https://archiveofourown.org/users/MissMollyBloom/pseuds/MissMollyBloom
Summary: So the trailer got in my head and delivered this little plot bunny. Probably a multi-chapter. We'll see.
What is Sherlock's "Darkest Secret"? How did he hide it from John Watson for so long? And how has it led to Molly Hooper being kidnapped and held hostage by Smith?





	1. Chapter 1

**Author's Note:**

> Woke up this morning (local time), watched the trailer, lost my mind, convinced myself that Sherlock is saying "I love you" to Molly, and then wrote the beginning of a new fic.
> 
> Enjoy!

“What’s the very worst thing you can do to your very best friends?” Smith taunted, “Tell them your darkest secret.”

“What the hell does he mean, Sherlock?” There was no masking the confusion in John Watson’s voice.

Of course John would be confused by Smith’s taunts. Living with Sherlock for years, of course John would assume that he had seen the best and the worst of him.

Of course, he’d be wrong.

Smith, mouth beaming in a grin so large, yet so frightening in its menace, began to chuckle, a cold, joyless, laugh.

“It’s a wonderful story, Mr Watson, full of passion, and intrigue, and lies,” turning to Sherlock, Smith asked, “would you like me to tell it?”

“N-no,” Sherlock hated how his voice cracked on the single syllable, betraying his attempt at a calm façade. He steeled himself, pulling himself up to a full height that towered over   
the diminutive figure of Smith. “I will do it.”

“Well, then you better get started,” Smith gestured to the clock on the wall, using his pistol as if it were a pointer rather than a deadly weapon. “The clock’s ticking!”

And so Sherlock began.

The story he began to tell Watson was a story that had taken place right under his best friend’s nose, one that John Watson for all his seeing had never perceived, never guessed.

Not because of any failure on the part of Sherlock’s friend, but by the deliberate design of the detective himself.

Because if there was one thing Sherlock always knew was that how important it would be that the one person who mattered most to him was considered by everyone else to be the one person who didn’t matter at all.

And now, with Smith with a gun to Sherlock’s head, and the one person who mattered most had been taken, hidden by Smith, and facing what could be the final hours of her life, it was time to come clean.

After all, all the lies they had told were meant to keep her safe from threats like this. Maybe the truth could set her free.

He thought of explaining all of this to John, weaving a tale dating back to the beginning, painting a picture of how it began, where and when and, most importantly, why and how he had kept it all for his best friend for so long.

But Sherlock Holmes wasn’t always one for poetry, especially when there was a chance to be dramatic. And so he blurted out, as fast as he could, “Molly and I have secretly been married for over 10 years and now Smith has her hostage so it’s time to come clean.”

John stared as his friend, slack-jawed, eyes wide.

“Sorry, what? Married?” John eyed Smith, of all people, for confirmation. The weasel-faced man merely nodded, the smirk playing across his face.

“Yes John. Molly is m-“ 

John cut him off, “Your wife? Married? You? How?”

“Well, we went to the registry office one Saturday morning, signed some papers, and that’s it. You really don’t need a whole church with dinner and speeches, you know.”  
John rolled his eyes, “I didn’t mean how you got married, I mean-“

“He wants to know how you hid it from him for so long,” Smith cut in.

John turned to Smith, “Yes, I’m quite capable of speaking for myself thankyou,”

“Temper, Temper!” Smith tutted.

“Well that-“ Sherlock paused for a moment, “that’s a much longer story.”

\---

Like anything to do with Sherlock Holmes, the story of how he and Molly met was nothing out of the ordinary. No usual meet-cute, or whatever it was called in ridiculous romantic films. 

Unless it was cute to meet the future love of your life while she tested your piss for drug use.

At the time, both Sherlock and Molly were students at King’s College. Sherlock, so close to being drummed out of his course for failure to attend – although, as he kept arguing, not out of any failure in his marks, which were the highest in the grade, had been given one final chance to graduate.

And it all rested on a piss-test. A piss-test administered by a second-year pathology student who worked as an assistant in the pathology department to help pay for her degree. 

“Not everyone’s parents have an infinite supply of money,” she’d later wryly informed him.

Even later still, did Sherlock learn that her father’s cancer treatment had cost him not only his life savings and his fund for Molly’s university, but the family home as well. 

“Can you tell me the results now?” he smiled, his best, most charming smile. The one he usually only reserved for the times between cocaine benders when sex became his replacement addiction.

But, even though he did admit to himself that the petite woman in front of him was attractive, something told him that she was not one who would take kindly to a one-night-stand, and that was the only kind of relationship Sherlock knew.

But maybe, just maybe, if he played his cards right, she could be the solution to his problem, the way to keep his habit from getting him drummed out of college.

Molly’s cheeks reddened under his intense gaze. She self-consciously tucked an errant strand of hair behind her ear.

“It usually takes ten minutes for the test to run.”

Sherlock smiled again, “I’m happy to wait. Maybe you can keep me company?”

They talked about their studies, their opinions on lecturers, and their expectations for the coming finals.

When the clock chimed, Sherlock had almost forgotten why he was there in the first place, and why it was that he was pretending to find her so interesting.

He realised later that the act was so easy because it was no act.

“I’m sorry, it’s positive. Not what you were hoping for.”

“No, my brother made a deal with the head of Chemistry – I won’t be kicked out if I pass a drugs test.”

“But you’re a Chemistry major, surely you knew you’d fail.”

“I was hoping for a miracle.”

“I’m sorry”

“You don’t think-“ he paused for effect, although aware that everything he was about to say was part of his plan all along, “You couldn’t just change the results in your report, could you?”

Molly’s eyes went wide. Fury rose like a red bloom, colouring her cheeks.

“You think you can come in here with your compliments and your big flirty eyes and your stories of woe and I’ll lie for you?”

Sherlock was shocked. This was the first time someone had seen through him. Had seen him.

“I’m sorry. Molly, truly I am,”

“The only way I will give you a clean test is if you test clean, do you understand?”

“Yes.”

And so it was that the first time Sherlock quit drugs, it was because of the insistence of Molly Hooper.


	2. Chapter 2

**Notes for the Chapter:**

> Thanks for the lovely comments and encouragement. I hope I can live up to the expectation! Here's part 2!

John Watson couldn’t believe what he was hearing. Sherlock. Married. To Molly Hooper. For a decade.

It was all so unbelievable. He didn’t know where to start, although, there was one question that popped into mind.

“There’s a long way from a piss test to the marriage aisle-”

  
“-registry office,” Sherlock corrected.

“Whatever.” John’s brow was furrowed, clearly he was still attempting to process the revelation. “So, what happened?” he asked.

“Desperation,” Smith grinned, his presence a horrible reminder of the reason the truth was finally coming to light.

* * *

 

Sherlock had finished university and found himself at a loss. And a mind like Sherlock’s without stimulation was a dangerous thing – for himself as well as others.

And so it was that after years of drifting in and out of crack dens, on an off cocaine, heroin and whatever Sherlock could get his hands on, it was Mycroft who put a stop to Sherlock’s spiral – by putting his food down, crushing the very thing that had enabled Sherlock’s habits.

“I’m cutting you off, little brother.”

Mycroft’s eyes narrowed as he looked Sherlock up and down. Sherlock knew there was no hiding the telltale signs, the dark lines under his eyes the layers of grease through his unwashed hair, the way his jeans hung loosely from his hips from the accumulation of days, sometimes weeks, without food.

It didn’t take a genius like Mycroft homes to tell that Sherlock was using again.

“Just give me one last chance,” Sherlock hated begging, but there was no other way.

“I’ve given you more than your fair share of last chances.”

“But I’ve got nowhere else to go!” Sherlock protested.

Mycroft smirked, “well, we both know that isn’t true.”

“Please no, anything but-“

“I think at this point, there’s only one person alive who has enough power to slap any sense into that addled head of yours.”

Sherlock sighed, resigned.“I know. That’s what I’m worried about.”

* * *

  
Molly had graduated with high enough marks to ensure easy entry into the prestigious residency program at Bart’s Hospital, yet, as she stared at herself in the hallway mirror, making the final adjustments to her hair and her blouse before leaving for her first day, she was struck with the same fear she had on her first day at King’s College –  
\- what if it’s some kind of mistake? What if they realise there are a thousand more qualified graduate pathologists in England? Or what if there was a mix-up? Hooper was a pretty common surname, maybe the papers got filed wrong and there she’ll be, ready to being the first day of the rest of her life, only to discover she had taken the spot of another M. Hooper – Mark or Mathew or Mary.

Molly was so lost in her thoughts that she didn’t even notice the sounds of someone picking the lock on her front door. She didn’t realise the nob turning or the door opening until she stepped straight into the chest of a man she hadn’t seen in over two years.

“Sherlock!”

“Hello Molly,” he said, eyes bowed, contrite, a new look for him.

Molly looked him up and down – unshaved, unkempt, unwashed hair – another new look.

But oddly familiar. Infuriatingly so.

“Mycroft cut you off?”

“Yep,” he said, his cheeks puffing out a popping sound on the p. A casual attempt to diffuse the tension.

It didn’t work.

“And you think you can waltz back in here and take up where we left off?”

“Not quite where we left off. From memory, where we left off was you shoving me out the door and onto the street.”

“And that’s what I’m about to do now.” Molly began trying to turn Sherlock’s considerably taller frame around and push him out the door, but even with his weightloss, which Molly could tell from the shallowness in his cheek and the even more server angles in his face, he definitely had the advantage.

Sherlock braced his arms on either side of the door, “Just, please, Molly. Hear me out?”

Molly exhaled deeply. “Fine.”

“I have a problem,” Sherlock said.

“Finally! You’re admitting to it.”

“No.” Molly’s eyes narrowed, she was about to open her mouth and bid him one final goodbye before he continues, “Well, yes, the drugs – but I have another problem.”

“Which is?”

“Trust fund. Held, in trust.”

“That’s not a problem, that’s just sensible money-management.”

“Yes, well, you have a problem too.”

“Which is?”

“You’re a low-paid pathology resident living in the world’s most expensive city. Your dad left you no inheritance, and as small as this excuse for a flat is, you’re still about to miss another rent payment.”

Her calm facade cracked, the truth of her hopeless situation laid bare. “I thought I could pick up extra hours on the side.”

Sherlock smiled the wry smile of a know it all. Molly's hand's curled into fists that even she didn't realise she was making. “On the side of a 70 hour a week residency program?”

“So, what’s it got to do with you?”

“This.” Out of his pocket, Sherlock pulled a rumpled document. He turned a few pages and pointed at a paragraph he’d underlined in red ink.

“This trust is only to be released on the thirtieth birthday of the undersigned party, or until such time as said party enters into a marital relationship – whichever comes first.”

“Two birds, one stone,” Sherlock grinned.

Molly stared at him for a moment, and Sherlock was almost amazed by how easy it was going to be. He was already planning what he would do with his first trust payment-

-when Molly slammed the door in his face.

  
\--  
“Ever the romantic,” John rolled his eyes.

  
“Well, that’s not actually how I proposed.”

“Please don’t tell me there were flowers and candles and a string quartet?”

  
“No, the only accompaniment was the sound of Molly’s landlord, knocking on the door to deliver an eviction notice.”

  
“Lovely.”

  
“But she did have two conditions.”

“What were they?”

  
“Condition one: no drugs.”

  
“How long till you broke that one?” John didin't know why he was asking - he knew what Sherlock's addictions were like.

  
“Only one month.”

  
“And the other condition?” John asked.

  
“Condition two: It was strictly a marriage of convenience. There was to be, under no circumstances, any sex.”

  
“And when did you break that one?” John measured his words, unsure if he wanted to know the answer.

  
“Even sooner,” Sherlock admitted, unable to stop himself smiling at the memory.


	3. Chapter 3

**Notes for the Chapter:**

> I've got a ridiculous amount of WiPs - and I really should do something about it. So I'm going to work through the list and update them whenever I'm able.
> 
> This WiP was my s4 trailer reaction fic. Interesting to see how confident I was in the "I Love You" way back when! So I'm going to keep going, but clearly this is now an Alternate version of s4 - instead of Eurus holding Sherlock and John at Sherrinford, it's Culverton Smith.
> 
> More details to come as I write them!! Enjoy.

Stuck in a small 5x12 cell with no exit beyond that which Culverton Smith offered, and that would certainly be at the mercy of his Sig Sauer revolver, Sherlock began to grow frustrated. But his frustration was only matched by that of his friend, desperate to discover how it was that Sherlock and Molly had been able to keep their secret for so long.

"So you and Molly - you - I mean - you've-" John couldn't being himself to say the words. For years he'd been convinced that his friend was a virgin. And after the Irene Adler affair, John had never even considered that there was anyone other than "The Woman" as Sherlock had dubbed the dominatrix who, at least from John's perspective, had dominated the great detective's mind as well as his heart. So the news that not only had Sherlock and Molly been engaged in a marriage of convenience upended all of John's preconceived notions about his friend, John Watson, blogger extraordinaire found himself unable to grasp the words to describe the possibility that Sherlock and Molly had-

"They've been running around shagging behind your back for years," Smith sneered, and laughed in a mirthless chortle.

With that, John could see Sherlock's frustration run over.

"I don't really see the point in rehashing ancient history."

Smith's face grew serious, his eyes piercing like the snake he was.

"You and I both know Mr Holmes that you paid a visit to your wife just the other night. She was in need of some comfort after-" Smith gestured towards John. The mere suggestion of his wife's death by this man was enough to set the former soldier on edge.

"Don't you dare," John rushed forward to grab Smith by the lapels. Sherlock held his friend back. It took a few repeats of his name for John to realise that Sherlock was holding him back, trying to calm him down.

"That's not the way it's going to work," Sherlock explained in measured, calm tones.

"Then what do you want?" John asked Culverton who surveyed the pair with the interest of a biologist surveying a new specimen.

"I want him to tell you everything he's kept from you. I want him to watch while you discover that the great Sherlock Holmes you've been blogging about for all these years is a liar, a cheat and a murderer."

John searched his friend's eyes for proof that what Smith was saying was untrue. All he was was sadness and resignation.

"Where should I start?" Sherlock deferred to Smith, an admission that he was the man in the room with all the power - and held a weapon more powerful than any gun. He had the truth.

"Start on your wedding night," Smith laughed, "and don't spare the details."

* * *

 

 

Their wedding wasn't a ceremony. It wasn't a celebration. It was a legal procedure akin to opening a bank account or filing an income tax return. There were no rings, no declarations of love, only a solemn realisation that the fates of these two former friends were now bound together.

Molly had come straight from Bart's, Sherlock could smell the lemon scented handwash she used to cover the stench of the morgue as he walked with her down the courthouse steps. Sherlock was wearing jeans that were a size and a half too large, a result of his recent weightloss, and a t-shirt he had grabbed from the back of his wardrobe and put on so hastily that he didn't notice how threadbare it was.

They walked in silence to the tube, Molly stared blankly at their fellow commuters, Sherlock's mind was blank as to what to say.

It was only as they walked towards the small Montague Street flat that was once Molly's but would now be theirs, that Molly spoke up.

She gestured to the Tesco's on the corner, "I need to buy some things," she said.

Sherlock only nodded. He waited outside, smoking two cigarettes while she shopped. It would still be a few more days until his trust fund came through, even though he had taken the liberty of faxing his marriage certificate to Mycroft the moment it was certified - charming the clerk behind the counter for access to the fax machine.

Moments after Sherlock had finished cigarette number 2, Molly exited the shop. There was no mistaking the clinking sound of the cheap red wine bottles stuffed into two plastic bags.

"It's my wedding night - probably the only one I'm going to have. So I'm  _celebrating_ it my way." She spat out the word with such bitterness that for the first time Sherlock wondered if they'd made a mistake.

Two and a half bottles later, Sherlock's fears were confirmed, but not for the reasons he had thought.

Sherlock was laughing. Drunk Molly was funny, or at least Drunk Molly told jokes that Drunk Sherlock thought were funny.

Drunk Molly also liked dancing. She had dug out an old hits of the 1990s and was swaying along to the UB40 version of "Baby I Love your Way". Half way through the song, she waved at him to join her. He knew he shouldn't, but there was something about the petite resident pathologist that drew him to her. 

As they danced, Molly with her hands around Sherlock's neck and Sherlock with his arms resting on her hips, Molly whispered something almost unintelligible.

It was only in the morning, when he awoke, naked, entangled with his body wrapped protectively around the also-naked body of his wife, that Sherlock remembered what she had said.

"I might be married to you Sherlock, but I will never sleep with you."

As it turned out, Molly was wrong.

 


End file.
